Field of the Invention
The present invention relates to an assembly structure of a roller, and more particularly, to an assembly structure of a roller in which a ring fit on a shaft does not cause slip relative to the shaft.
Background Art
Rollers are cylindrical bodies which are used to compress and transform things or to help movement of things. For instance, there are rolling rollers as representative rollers for compressing and transforming things.
The conventional rolling roller includes a shaft manufactured integrally to receive rotary power. However, such a conventional rolling roller has several disadvantages in that it causes lots of economic losses and it is difficult to work due to its heavy weight because the rolling roller must be replaced or repaired integrally when the surface of the roller is damaged during rolling work.
In order to solve the problems, Korean Patent Laid-open No. 10-2012-0070208 discloses a rolling roller 1, in which a part to compress a workpiece is disposed to be separated by a ring unit 20 formed in a hollow cylindrical shape and is forcedly fit to a shaft 10 so that only the ring unit 20 can be separately replaced and repaired. (See FIG. 1)
The ‘ring unit’ of the rolling roller 1 is called a ‘rolling ring’, and in the present invention, the ‘ring unit’ will be also called the ‘rolling ring’.
Such a rolling roller 1 includes a clamp 40 for pressing the rolling ring 20, which is fit to the shaft, toward a collar unit 30 or a spacer 50. Finally, rotary power of the shaft 10 is transferred to the rolling ring 20 when the clamp 40 fixed to the shaft 10 comes into contact with a side portion of the rolling ring 20 to press the side portion of the rolling ring 20. However, frictional force between the rolling ring 20 and the workpiece causes a slip between the rolling ring 20 and the shaft 10, such that the surface of the workpiece becomes bad and the rolling roller is damaged.
In order to solve the above-mentioned problem, as shown in FIG. 2, Korean Patent No. 10-0782751 discloses a structure that a collar unit 30 of a shaft 10 is processed to be inclined so as to interlock with an inclined side of a rolling ring 20. Additionally, Korean Patent No. 10-0782751 discloses a structure that a spacer located at the center has inclined surfaces disposed at both sides thereof in case that a rolling ring is divided into two.
However, such prior arts have several disadvantages in that it is complicated to form the inclined surfaces at the side of the rolling ring 20 and in that a mounting area of a caliber for rolling workpieces, such as wires or rods, inside a rolling mill 100 having a predetermined width as shown in FIG. 3 is reduced and productivity is deteriorated because the clamp 40 is mounted on the shaft 10 in a protrusion manner while getting in contact with the side of the rolling ring 20.